How to Create a Primary Key for a MySQL Database in Python

You can create a Primary Key for your MySQL database in Python as follows.

First, you need to know if the Primary Key already exists.

Option 1 – The Primary Key does not Exist

import mysql.connector

mydb = mysql.connector.connect(
  host = "localhost",
  user = "username",
  password = "YoUrPaSsWoRd",
  database = "your_database"
)

mycursor = mydb.cursor()

mycursor.execute("CREATE TABLE customers (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), address VARCHAR(255))")

Option 2 – The Primary Key already Exists

import mysql.connector

mydb = mysql.connector.connect(
  host = "localhost",
  user = "username",
  password = "YoUrPaSsWoRd",
  database = "your_database"
)

mycursor = mydb.cursor()

mycursor.execute("ALTER TABLE customers ADD COLUMN id INT AUTO_INCREMENT PRIMARY KEY")